Can anyone tell me if using an OC in ati overdrive invalidate the warranty? I tried it once and then just went back to factory settings because the GPU would only OC by 10 mhz and the benefits were negligable (I know the cards got a factory OC but I thought this was quite a duff OC). I have a sapphire 4870 toxic 1 gig, and i am getting artifacts and some games are crashing. I used the' Xtreme burning mode' in fur mark to test the card and after 2 seconds i am getting jaggies.
If it was an Nvidia card, I would say that the shader clock is too high, but then it would have been a black triangle.